summaryrefslogtreecommitdiff
path: root/src/libstrongswan/crypto/rsa/rsa_private_key.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libstrongswan/crypto/rsa/rsa_private_key.c')
-rw-r--r--src/libstrongswan/crypto/rsa/rsa_private_key.c722
1 files changed, 0 insertions, 722 deletions
diff --git a/src/libstrongswan/crypto/rsa/rsa_private_key.c b/src/libstrongswan/crypto/rsa/rsa_private_key.c
deleted file mode 100644
index 1b1499887..000000000
--- a/src/libstrongswan/crypto/rsa/rsa_private_key.c
+++ /dev/null
@@ -1,722 +0,0 @@
-/**
- * @file rsa_private_key.c
- *
- * @brief Implementation of rsa_private_key_t.
- *
- */
-
-/*
- * Copyright (C) 2005 Jan Hutter
- * Copyright (C) 2005-2006 Martin Willi
- * Copyright (C) 2007-2008 Andreas Steffen
- *
- * Hochschule fuer Technik Rapperswil
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * RCSID $Id: rsa_private_key.c 3429 2008-01-27 20:59:22Z andreas $
- */
-
-#include <gmp.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <string.h>
-
-#include "rsa_public_key.h"
-#include "rsa_private_key.h"
-
-#include <debug.h>
-#include <asn1/asn1.h>
-#include <asn1/pem.h>
-#include <utils/randomizer.h>
-
-/**
- * defined in rsa_public_key.c
- */
-extern chunk_t rsa_public_key_info_to_asn1(const mpz_t n, const mpz_t e);
-extern chunk_t rsa_public_key_id_create(const mpz_t n, const mpz_t e);
-
-/**
- * Public exponent to use for key generation.
- */
-#define PUBLIC_EXPONENT 0x10001
-
-typedef struct private_rsa_private_key_t private_rsa_private_key_t;
-
-/**
- * Private data of a rsa_private_key_t object.
- */
-struct private_rsa_private_key_t {
- /**
- * Public interface for this signer.
- */
- rsa_private_key_t public;
-
- /**
- * Version of key, as encoded in PKCS#1
- */
- u_int version;
-
- /**
- * Public modulus.
- */
- mpz_t n;
-
- /**
- * Public exponent.
- */
- mpz_t e;
-
- /**
- * Private prime 1.
- */
- mpz_t p;
-
- /**
- * Private Prime 2.
- */
- mpz_t q;
-
- /**
- * Private exponent.
- */
- mpz_t d;
-
- /**
- * Private exponent 1.
- */
- mpz_t exp1;
-
- /**
- * Private exponent 2.
- */
- mpz_t exp2;
-
- /**
- * Private coefficient.
- */
- mpz_t coeff;
-
- /**
- * Keysize in bytes.
- */
- size_t k;
-
- /**
- * Keyid formed as a SHA-1 hash of a publicKeyInfo object
- */
- chunk_t keyid;
-
- /**
- * @brief Implements the RSADP algorithm specified in PKCS#1.
- *
- * @param this calling object
- * @param data data to process
- * @return processed data
- */
- chunk_t (*rsadp) (private_rsa_private_key_t *this, chunk_t data);
-
- /**
- * @brief Implements the RSASP1 algorithm specified in PKCS#1.
- * @param this calling object
- * @param data data to process
- * @return processed data
- */
- chunk_t (*rsasp1) (private_rsa_private_key_t *this, chunk_t data);
-};
-
-/* ASN.1 definition of a PKCS#1 RSA private key */
-static const asn1Object_t privkey_objects[] = {
- { 0, "RSAPrivateKey", ASN1_SEQUENCE, ASN1_NONE }, /* 0 */
- { 1, "version", ASN1_INTEGER, ASN1_BODY }, /* 1 */
- { 1, "modulus", ASN1_INTEGER, ASN1_BODY }, /* 2 */
- { 1, "publicExponent", ASN1_INTEGER, ASN1_BODY }, /* 3 */
- { 1, "privateExponent", ASN1_INTEGER, ASN1_BODY }, /* 4 */
- { 1, "prime1", ASN1_INTEGER, ASN1_BODY }, /* 5 */
- { 1, "prime2", ASN1_INTEGER, ASN1_BODY }, /* 6 */
- { 1, "exponent1", ASN1_INTEGER, ASN1_BODY }, /* 7 */
- { 1, "exponent2", ASN1_INTEGER, ASN1_BODY }, /* 8 */
- { 1, "coefficient", ASN1_INTEGER, ASN1_BODY }, /* 9 */
- { 1, "otherPrimeInfos", ASN1_SEQUENCE, ASN1_OPT |
- ASN1_LOOP }, /* 10 */
- { 2, "otherPrimeInfo", ASN1_SEQUENCE, ASN1_NONE }, /* 11 */
- { 3, "prime", ASN1_INTEGER, ASN1_BODY }, /* 12 */
- { 3, "exponent", ASN1_INTEGER, ASN1_BODY }, /* 13 */
- { 3, "coefficient", ASN1_INTEGER, ASN1_BODY }, /* 14 */
- { 1, "end opt or loop", ASN1_EOC, ASN1_END } /* 15 */
-};
-
-#define PRIV_KEY_VERSION 1
-#define PRIV_KEY_MODULUS 2
-#define PRIV_KEY_PUB_EXP 3
-#define PRIV_KEY_PRIV_EXP 4
-#define PRIV_KEY_PRIME1 5
-#define PRIV_KEY_PRIME2 6
-#define PRIV_KEY_EXP1 7
-#define PRIV_KEY_EXP2 8
-#define PRIV_KEY_COEFF 9
-#define PRIV_KEY_ROOF 16
-
-/**
- * Auxiliary function overwriting private key material with
- * pseudo-random bytes before releasing it
- */
-static void mpz_clear_randomized(mpz_t z)
-{
- size_t len = mpz_size(z) * GMP_LIMB_BITS / BITS_PER_BYTE;
- u_int8_t *random_bytes = alloca(len);
-
- randomizer_t *randomizer = randomizer_create();
-
- randomizer->get_pseudo_random_bytes(randomizer, len, random_bytes);
-
- /* overwrite mpz_t with pseudo-random bytes before clearing it */
- mpz_import(z, len, 1, 1, 1, 0, random_bytes);
- mpz_clear(z);
-
- randomizer->destroy(randomizer);
-}
-
-/**
- * Generate a random prime number with prime_len bytes
- */
-static status_t compute_prime(private_rsa_private_key_t *this, size_t prime_len, mpz_t *prime)
-{
- randomizer_t *randomizer;
- chunk_t random_bytes;
- status_t status;
-
- randomizer = randomizer_create();
- mpz_init(*prime);
-
- do
- {
- DBG1(" generating %d bit prime from %s ...", BITS_PER_BYTE * prime_len, DEV_RANDOM);
- status = randomizer->allocate_random_bytes(randomizer, prime_len, &random_bytes);
- if (status != SUCCESS)
- {
- randomizer->destroy(randomizer);
- mpz_clear(*prime);
- return FAILED;
- }
-
- /* make sure most significant bit is set */
- random_bytes.ptr[0] = random_bytes.ptr[0] | 0x80;
-
- /* convert chunk to mpz value */
- mpz_import(*prime, random_bytes.len, 1, 1, 1, 0, random_bytes.ptr);
-
- /* get next prime */
- mpz_nextprime (*prime, *prime);
-
- /* free the random_bytes after overwriting them with a pseudo-random sequence */
- chunk_free_randomized(&random_bytes);
- }
- /* check if it isnt too large */
- while (((mpz_sizeinbase(*prime, 2) + 7) / BITS_PER_BYTE) > prime_len);
-
- randomizer->destroy(randomizer);
- return SUCCESS;
-}
-
-/**
- * Implementation of private_rsa_private_key_t.rsadp and private_rsa_private_key_t.rsasp1.
- */
-static chunk_t rsadp(private_rsa_private_key_t *this, chunk_t data)
-{
- mpz_t t1, t2;
- chunk_t decrypted;
-
- mpz_init(t1);
- mpz_init(t2);
-
- mpz_import(t1, data.len, 1, 1, 1, 0, data.ptr);
-
- mpz_powm(t2, t1, this->exp1, this->p); /* m1 = c^dP mod p */
- mpz_powm(t1, t1, this->exp2, this->q); /* m2 = c^dQ mod Q */
- mpz_sub(t2, t2, t1); /* h = qInv (m1 - m2) mod p */
- mpz_mod(t2, t2, this->p);
- mpz_mul(t2, t2, this->coeff);
- mpz_mod(t2, t2, this->p);
-
- mpz_mul(t2, t2, this->q); /* m = m2 + h q */
- mpz_add(t1, t1, t2);
-
- decrypted.len = this->k;
- decrypted.ptr = mpz_export(NULL, NULL, 1, decrypted.len, 1, 0, t1);
-
- mpz_clear_randomized(t1);
- mpz_clear_randomized(t2);
-
- return decrypted;
-}
-
-/**
- * Implementation of rsa_private_key_t.pkcs1_decrypt.
- */
-static status_t pkcs1_decrypt(private_rsa_private_key_t *this,
- chunk_t in, chunk_t *out)
-{
- status_t status = FAILED;
- chunk_t em, em_ori;
-
- /* decrypt the input data */
- em = em_ori = this->rsadp(this, in);
-
- /* PKCS#1 v1.5 EME encryption formatting
- * EM = 00 || 02 || PS || 00 || M
- * PS = pseudo-random nonzero octets
- */
-
- /* check for magic bytes */
- if (*(em.ptr) != 0x00 || *(em.ptr+1) != 0x02)
- {
- DBG1("incorrect padding - probably wrong RSA key");
- goto end;
- }
- em.ptr += 2;
- em.len -= 2;
-
- /* the plaintext data starts after first 0x00 byte */
- while (em.len-- > 0 && *em.ptr++ != 0x00);
-
- if (em.len == 0)
- {
- DBG1("no plaintext data found");
- goto end;
- }
-
- *out = chunk_clone(em);
- status = SUCCESS;
-
-end:
- free(em_ori.ptr);
- return status;
-}
-
-/**
- * Implementation of rsa_private_key_t.build_emsa_pkcs1_signature.
- */
-static status_t build_emsa_pkcs1_signature(private_rsa_private_key_t *this,
- hash_algorithm_t hash_algorithm,
- chunk_t data, chunk_t *signature)
-{
- hasher_t *hasher;
- chunk_t em, digestInfo, hash;
- int hash_oid = hasher_algorithm_to_oid(hash_algorithm);
-
- if (hash_oid == OID_UNKNOWN)
- {
- return NOT_SUPPORTED;
- }
-
- /* get hasher */
- hasher = hasher_create(hash_algorithm);
- if (hasher == NULL)
- {
- return NOT_SUPPORTED;
- }
-
- /* build hash */
- hasher->allocate_hash(hasher, data, &hash);
- hasher->destroy(hasher);
-
- /* build DER-encoded digestInfo */
- digestInfo = asn1_wrap(ASN1_SEQUENCE, "cm",
- asn1_algorithmIdentifier(hash_oid),
- asn1_simple_object(ASN1_OCTET_STRING, hash)
- );
- chunk_free(&hash);
-
- /* build chunk to rsa-decrypt:
- * EM = 0x00 || 0x01 || PS || 0x00 || T.
- * PS = 0xFF padding, with length to fill em
- * T = encoded_hash
- */
- em.len = this->k;
- em.ptr = malloc(em.len);
-
- /* fill em with padding */
- memset(em.ptr, 0xFF, em.len);
- /* set magic bytes */
- *(em.ptr) = 0x00;
- *(em.ptr+1) = 0x01;
- *(em.ptr + em.len - digestInfo.len - 1) = 0x00;
- /* set DER-encoded hash */
- memcpy(em.ptr + em.len - digestInfo.len, digestInfo.ptr, digestInfo.len);
-
- /* build signature */
- *signature = this->rsasp1(this, em);
-
- free(digestInfo.ptr);
- free(em.ptr);
-
- return SUCCESS;
-}
-
-/**
- * Implementation of rsa_private_key_t.pkcs1_write.
- */
-static bool pkcs1_write(private_rsa_private_key_t *this, const char *filename, bool force)
-{
- bool status;
-
- chunk_t pkcs1 = asn1_wrap(ASN1_SEQUENCE, "cmmmmmmmm",
- ASN1_INTEGER_0,
- asn1_integer_from_mpz(this->n),
- asn1_integer_from_mpz(this->e),
- asn1_integer_from_mpz(this->d),
- asn1_integer_from_mpz(this->p),
- asn1_integer_from_mpz(this->q),
- asn1_integer_from_mpz(this->exp1),
- asn1_integer_from_mpz(this->exp2),
- asn1_integer_from_mpz(this->coeff));
-
- status = chunk_write(pkcs1, filename, "pkcs1", 0066, force);
- chunk_free_randomized(&pkcs1);
- return status;
-}
-
-/**
- * Implementation of rsa_private_key_t.get_public_key.
- */
-rsa_public_key_t *get_public_key(private_rsa_private_key_t *this)
-{
- return rsa_public_key_create(this->n, this->e);
-}
-
-/**
- * Implementation of rsa_private_key.belongs_to.
- */
-static bool belongs_to(private_rsa_private_key_t *this, rsa_public_key_t *public)
-{
- return chunk_equals(this->keyid, public->get_keyid(public));
-}
-
-/**
- * Check the loaded key if it is valid and usable
- * TODO: Log errors
- */
-static status_t check(private_rsa_private_key_t *this)
-{
- mpz_t t, u, q1;
- status_t status = SUCCESS;
-
- /* PKCS#1 1.5 section 6 requires modulus to have at least 12 octets.
- * We actually require more (for security).
- */
- if (this->k < 512 / BITS_PER_BYTE)
- {
- return FAILED;
- }
-
- /* we picked a max modulus size to simplify buffer allocation */
- if (this->k > 8192 / BITS_PER_BYTE)
- {
- return FAILED;
- }
-
- mpz_init(t);
- mpz_init(u);
- mpz_init(q1);
-
- /* check that n == p * q */
- mpz_mul(u, this->p, this->q);
- if (mpz_cmp(u, this->n) != 0)
- {
- status = FAILED;
- }
-
- /* check that e divides neither p-1 nor q-1 */
- mpz_sub_ui(t, this->p, 1);
- mpz_mod(t, t, this->e);
- if (mpz_cmp_ui(t, 0) == 0)
- {
- status = FAILED;
- }
-
- mpz_sub_ui(t, this->q, 1);
- mpz_mod(t, t, this->e);
- if (mpz_cmp_ui(t, 0) == 0)
- {
- status = FAILED;
- }
-
- /* check that d is e^-1 (mod lcm(p-1, q-1)) */
- /* see PKCS#1v2, aka RFC 2437, for the "lcm" */
- mpz_sub_ui(q1, this->q, 1);
- mpz_sub_ui(u, this->p, 1);
- mpz_gcd(t, u, q1); /* t := gcd(p-1, q-1) */
- mpz_mul(u, u, q1); /* u := (p-1) * (q-1) */
- mpz_divexact(u, u, t); /* u := lcm(p-1, q-1) */
-
- mpz_mul(t, this->d, this->e);
- mpz_mod(t, t, u);
- if (mpz_cmp_ui(t, 1) != 0)
- {
- status = FAILED;
- }
-
- /* check that exp1 is d mod (p-1) */
- mpz_sub_ui(u, this->p, 1);
- mpz_mod(t, this->d, u);
- if (mpz_cmp(t, this->exp1) != 0)
- {
- status = FAILED;
- }
-
- /* check that exp2 is d mod (q-1) */
- mpz_sub_ui(u, this->q, 1);
- mpz_mod(t, this->d, u);
- if (mpz_cmp(t, this->exp2) != 0)
- {
- status = FAILED;
- }
-
- /* check that coeff is (q^-1) mod p */
- mpz_mul(t, this->coeff, this->q);
- mpz_mod(t, t, this->p);
- if (mpz_cmp_ui(t, 1) != 0)
- {
- status = FAILED;
- }
-
- mpz_clear_randomized(t);
- mpz_clear_randomized(u);
- mpz_clear_randomized(q1);
- return status;
-}
-
-/**
- * Implementation of rsa_private_key.destroy.
- */
-static void destroy(private_rsa_private_key_t *this)
-{
- mpz_clear_randomized(this->n);
- mpz_clear_randomized(this->e);
- mpz_clear_randomized(this->p);
- mpz_clear_randomized(this->q);
- mpz_clear_randomized(this->d);
- mpz_clear_randomized(this->exp1);
- mpz_clear_randomized(this->exp2);
- mpz_clear_randomized(this->coeff);
- chunk_free_randomized(&this->keyid);
- free(this);
-}
-
-/**
- * Internal generic constructor
- */
-static private_rsa_private_key_t *rsa_private_key_create_empty(void)
-{
- private_rsa_private_key_t *this = malloc_thing(private_rsa_private_key_t);
-
- /* public functions */
- this->public.pkcs1_decrypt = (status_t (*) (rsa_private_key_t*,chunk_t,chunk_t*))pkcs1_decrypt;
- this->public.build_emsa_pkcs1_signature = (status_t (*) (rsa_private_key_t*,hash_algorithm_t,chunk_t,chunk_t*))build_emsa_pkcs1_signature;
- this->public.pkcs1_write = (bool (*) (rsa_private_key_t*,const char*,bool))pkcs1_write;
- this->public.get_public_key = (rsa_public_key_t* (*) (rsa_private_key_t*))get_public_key;
- this->public.belongs_to = (bool (*) (rsa_private_key_t*,rsa_public_key_t*))belongs_to;
- this->public.destroy = (void (*) (rsa_private_key_t*))destroy;
-
- /* private functions */
- this->rsadp = rsadp;
- this->rsasp1 = rsadp; /* same algorithm */
-
- this->keyid = chunk_empty;
-
- return this;
-}
-
-/*
- * See header
- */
-rsa_private_key_t *rsa_private_key_create(size_t key_size)
-{
- mpz_t p, q, n, e, d, exp1, exp2, coeff;
- mpz_t m, q1, t;
- private_rsa_private_key_t *this;
- size_t key_len = key_size / BITS_PER_BYTE;
- size_t prime_len = key_len / 2;
-
- /* Get values of primes p and q */
- if (compute_prime(this, prime_len, &p) != SUCCESS)
- {
- return NULL;
- }
- if (compute_prime(this, prime_len, &q) != SUCCESS)
- {
- mpz_clear(p);
- return NULL;
- }
-
- mpz_init(t);
- mpz_init(n);
- mpz_init(d);
- mpz_init(exp1);
- mpz_init(exp2);
- mpz_init(coeff);
-
- /* Swapping Primes so p is larger then q */
- if (mpz_cmp(p, q) < 0)
- {
- mpz_swap(p, q);
- }
-
- mpz_mul(n, p, q); /* n = p*q */
- mpz_init_set_ui(e, PUBLIC_EXPONENT); /* assign public exponent */
- mpz_init_set(m, p); /* m = p */
- mpz_sub_ui(m, m, 1); /* m = m -1 */
- mpz_init_set(q1, q); /* q1 = q */
- mpz_sub_ui(q1, q1, 1); /* q1 = q1 -1 */
- mpz_gcd(t, m, q1); /* t = gcd(p-1, q-1) */
- mpz_mul(m, m, q1); /* m = (p-1)*(q-1) */
- mpz_divexact(m, m, t); /* m = m / t */
- mpz_gcd(t, m, e); /* t = gcd(m, e) (greatest common divisor) */
-
- mpz_invert(d, e, m); /* e has an inverse mod m */
- if (mpz_cmp_ui(d, 0) < 0) /* make sure d is positive */
- {
- mpz_add(d, d, m);
- }
- mpz_sub_ui(t, p, 1); /* t = p-1 */
- mpz_mod(exp1, d, t); /* exp1 = d mod p-1 */
- mpz_sub_ui(t, q, 1); /* t = q-1 */
- mpz_mod(exp2, d, t); /* exp2 = d mod q-1 */
-
- mpz_invert(coeff, q, p); /* coeff = q^-1 mod p */
- if (mpz_cmp_ui(coeff, 0) < 0) /* make coeff d is positive */
- {
- mpz_add(coeff, coeff, p);
- }
-
- mpz_clear_randomized(q1);
- mpz_clear_randomized(m);
- mpz_clear_randomized(t);
-
- /* determine exact the modulus size in bits */
- key_size = mpz_sizeinbase(n, 2);
-
- /* create and fill in rsa_private_key_t object */
- this = rsa_private_key_create_empty();
- this->k = (key_size + 7) / BITS_PER_BYTE;
- this->keyid = rsa_public_key_id_create(n, e);
- *(this->p) = *p;
- *(this->q) = *q;
- *(this->n) = *n;
- *(this->e) = *e;
- *(this->d) = *d;
- *(this->exp1) = *exp1;
- *(this->exp2) = *exp2;
- *(this->coeff) = *coeff;
- DBG1("generated %d bit RSA key with keyid: %#B", key_size, &this->keyid);
-
- return &this->public;
-}
-
-/*
- * see header
- */
-rsa_private_key_t *rsa_private_key_create_from_chunk(chunk_t blob)
-{
- asn1_ctx_t ctx;
- chunk_t object;
- u_int level;
- int objectID = 0;
- private_rsa_private_key_t *this;
-
- this = rsa_private_key_create_empty();
-
- mpz_init(this->n);
- mpz_init(this->e);
- mpz_init(this->p);
- mpz_init(this->q);
- mpz_init(this->d);
- mpz_init(this->exp1);
- mpz_init(this->exp2);
- mpz_init(this->coeff);
-
- asn1_init(&ctx, blob, 0, FALSE, TRUE);
-
- while (objectID < PRIV_KEY_ROOF)
- {
- if (!extract_object(privkey_objects, &objectID, &object, &level, &ctx))
- {
- destroy(this);
- return FALSE;
- }
- switch (objectID)
- {
- case PRIV_KEY_VERSION:
- if (object.len > 0 && *object.ptr != 0)
- {
- destroy(this);
- return NULL;
- }
- break;
- case PRIV_KEY_MODULUS:
- mpz_import(this->n, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_PUB_EXP:
- mpz_import(this->e, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_PRIV_EXP:
- mpz_import(this->d, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_PRIME1:
- mpz_import(this->p, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_PRIME2:
- mpz_import(this->q, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_EXP1:
- mpz_import(this->exp1, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_EXP2:
- mpz_import(this->exp2, object.len, 1, 1, 1, 0, object.ptr);
- break;
- case PRIV_KEY_COEFF:
- mpz_import(this->coeff, object.len, 1, 1, 1, 0, object.ptr);
- break;
- }
- objectID++;
- }
-
- this->k = (mpz_sizeinbase(this->n, 2) + 7) / BITS_PER_BYTE;
- this->keyid = rsa_public_key_id_create(this->n, this->e);
-
- if (check(this) != SUCCESS)
- {
- destroy(this);
- return NULL;
- }
- else
- {
- return &this->public;
- }
-}
-
-/*
- * see header
- */
-rsa_private_key_t *rsa_private_key_create_from_file(char *filename, chunk_t *passphrase)
-{
- bool pgp = FALSE;
- chunk_t chunk = chunk_empty;
- rsa_private_key_t *key = NULL;
-
- if (!pem_asn1_load_file(filename, passphrase, "private key", &chunk, &pgp))
- return NULL;
-
- key = rsa_private_key_create_from_chunk(chunk);
- chunk_free_randomized(&chunk);
- return key;
-}